Mueller Using Grand Juries in Va. and D.C. in Trump-Russia Probe

Special Counsel Robert Mueller departs after briefing members of the U.S. Senate on his investigation of potential collusion between Russia and the Trump campaign on Capitol Hill on June 21, 2017 in Washington.Joshua Roberts / Reuters

Breaking News Emails

Get breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.

Aug. 4, 2017, 5:17 PM GMT / Updated Aug. 4, 2017, 5:17 PM GMT

By Keri Geiger and Tom Winter

Special Counsel Robert Mueller has tapped multiple grand juries, including juries in Washington and Virginia, in an effort to gather evidence in the ongoing federal investigation into Russia's meddling in the U.S. presidential election, three sources familiar with the matter told NBC News.

The Wall Street Journal reported Thursday that Mueller had impanelled a separate grand jury in Washington, but sources familiar with the matter say that Mueller is using existing grand juries in both Washington and Virginia.

Mueller was appointed the special counsel by the Justice Department in May to investigate links between President Donald Trump's presidential campaign and Russia. Mueller led the FBI for 12 years under presidents George W. Bush and Barack Obama. He is second only to J. Edgar Hoover for longest tenure for an FBI chief.

The use of a grand jury is part of the normal process of a complex investigation and it is a tool not just for hearing testimony but for learning about and obtaining records from individuals or companies. It is a powerful tool prosecutors can use to seek indictments and subpoenas, and may be a signal Mueller's work is far from over.

Records related to business transactions for former campaign chairman Paul Manafort and former National Security Advisor Michael Flynn are among the documents that have been subpoenaed through the grand jury process.

Law enforcement officials tell NBC News that both Flynn and Manafort are formally considered "subjects" of a criminal investigation, though their lawyers say they have done nothing wrong. A "subject" is someone whose conduct is being examined by the investigation, and may be suspected of a crime. So far, no public evidence has surfaced linking Flynn and Manafort to the Russian interference effort.

Keri Geiger

Keri Geiger is a financial investigative reporter with the NBC News Investigative Unit. She was previously a reporter at Bloomberg News, where she specialized in financial crime and national security. Prior to Bloomberg, she was a foreign correspondent for Euromoney and The Wall Street Journal. She worked at Deutsche Bank before entering journalism

Tom Winter

Tom Winter is a producer and reporter for the NBC News Investigative Unit based in New York, covering crime, courts, terrorism, and financial fraud on the East Coast.